Sandwich element and a load floor made as such an element

Abstract

A sandwich element (10) including a first restriction layer (21) and a second restriction layer (22) and a distance core (23) of a light weight material, preferably of a foam material, between said restriction layers, whereby the second restriction layer (22) includes stiffening elements (11) arranged in parallel with each other and individually or together with a corresponding abutting stiffening element (11) form a closed hollow profile (24). Furthermore the invention refers to a load floor shaped as such a sandwich element and also that such a load floor is a part of a cargo vehicle.

Description

[0001]This application is the U.S. national phase of International Application No. PCT / SE2014 / 050658 filed 28 May 2014, which designated the U.S. and claims priority to SE Patent Application No. 1350656-3 filed 30 May 2013, the entire contents of each of which are hereby incorporated by reference.TECHNICAL FIELD[0002]The present invention refers to the field of sandwich elements being provided with stiffening beams or profiles. Sandwich elements having such stiffening are above all suitable for load floors, e.g. in trucks, trailers and the like. The sandwich elements are of the type consisting of a foamed core as separate material between a first surface and a second surface.INTRODUCTION[0003]Through EP 1 457 408 a floor of a cargo space of a vehicle is known per se, e.g. of a truck or a trailer. The floor is built up with a horizontal lower support layer shaped as a profiled plate forming parallel webs having an even top side aimed at supporting an upper cover layer. The top cover ...

AI Technical Summary

Benefits of technology

[0008]The invention has in view to obtain a sandwich element being provided with a restriction layer including a closed hollow profile, which acts as a stiffening element. Such a closed hollow profile contributes to increase the rotation stiffness and the bending resistance as well of the sandwich element.

[0009]Furthermore the invention has in view to obtain a sandwich element having a thin core but provided with integrated stiffening elements at the underside. The advantages with such a sandwich element are that it has a low weight in that the two layers can be made with thin walls and in that the material of the core has low density and the layer including the stiffening elements is simple to produce by bending, pressing or rolling of a flat plate. It will stand heavier loads in proportion to its weight than the sandwich elements known as the material of the stiffening elements can be lead out from the core and in such a way contribute to a higher bending resistance of the sandwich element. Especially such sandwich elements are suitable for use as floors, which are affected of vertically directed loads and in particular as floors in cargo vehicles as the vertical directed loads on a vehicle floor tending to bend the vehicle floor are effectively accumulated by a bending resistive sandwich element shaped according to the invention. The advantages by such a sandwich element are on one hand that the stiffening elements are integrated with the second restriction layer of the sandwich element and on the other hand that a maximum material of the stiffening elements is at a distance from the thin core of the sandwich element.

[0013]According to an embodiment of the sandwich element the second restriction layer between two adjacent stiffening elements has the shape of a single bent surface. This embodiment accumulates loads in the element by introduction of compressive stress in a way corresponding to an arch at a bridge construction. In such a way the sandwich element can be made lighter for the same weight class.

[0014]According to another embodiment of the sandwich element the bent surface is positioned to have its greatest distance from the first restriction layer at the contact line in the second restriction layer. This embodiment distributes the compressive stress down into the stiffening elements.

[0018]The advantages with such triangular designed stiffening elements is to position as much material as possible as far from the centre of gravity as possible, which results in the best strength in the length direction. A closed hollow profile, irrespective of being triangular or having another cross section, results in a rotation rigid section contributing to a strength also in the weak direction, the cross direction. In such a way the core, mainly determining the strength in the cross direction, can be made thinner. In that the stiffening element is integrated in the lower, second restriction layer a more simple process is obtained which results in a more cost effective end product.

Problems solved by technology

This implies that the cover layer and thus all the floor will be rather heavy compared to the load it has to carry.

Furthermore the rivet joints or screw joints connecting the cover layer with the support layer will involve undesired indications of fracture in the cover layer.

Though the plate construction is in shape of a composite material it will be rather heavy compared to the load it has to carry.

Furthermore the method of supplying the filling to the areas confined by the webs and the layers is complicated and time consuming.

A problem of this previously known isolation element is that the triangular hollow profiles contribute only to a restricted reinforcement of the isolation element as they are placed inside the isolation element and having the even parallel side of the triangular hollow profiles close to the first restriction layer.

These isolation elements are not suitable for use as floors where the loads are considerably higher and still less suitable for floors in cargo vehicles having still higher loads.

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